I’ve tested a number of sites from TG and many others with Page Speed insights. I’ve adopted @eggs ideas with a graphical header for branding. And as roll ahead the % of phone browsing continues to rise. Admittedly I usually have my tablet in my lap; but I’m certainly not everyone.

The challenge is that people want to see pictures while phone browsing; or do they?? My designs are bordering on one image per page. Sure I’d like to add more, but I simply cannot. One makes images as small as possible but it’s a knife edge.

Perhaps phone browsing is for branding and contact only? Maybe viewers on phones want to see what a client does, and not what a client did? Xara would have most builders believe that a 1200px site, would have all those images on mobile; especially in a block format. I’d say respectively it’s incorrect.

Back to the question. How are important are images on mobile? How small should they be?
Are we obsessing with speed too much on mobile?